The invention relates to sports, games, and measuring devices.
It is difficult for the participants in practice for combat sports, in which the hands and arms are used as weapons, to determine the force with which a blow is struck. Presently this force is roughly judged by the reaction of a punching bag to a blow or an equivalent reaction pertaining to another sport, but this judgment is clearly rough and does not give the participant an accurate idea of whether his stroke is improving or worsening, and can be somewhat painful to the participant in karate practice who overestimates the number of bricks he can chop through.